The present invention relates to a cooling apparatus through which a coolant of the drive unit flows, and to which cooling air is supplied; the radiator is disposed in a separate compartment of a vehicle, especially an armored vehicle, above a cooling air fan. Openings in the roof and back end of the vehicle for supplying air to, and withdrawing air from, the cooling air fan are provided with gratings.
A cooling apparatus of the aforementioned general type is disclosed, for example, in German Offenlegungsschrift No. 27 37 595. When driving over terrain under normal conditions, this heretofore known device assures that atmospheric air is supplied to the radiator, and that the cooling air passes through uniformly. Furthermore, by disposing the cooling air fan below the radiator, dust and/or water which is raised or sprayed up from the roadway as the vehicle is moving, cannot be deposited on the housing of the radiator, so that after the water dries, the radiator housing is not covered with dirt, which would adversely affect the cooling. On the other hand, when the vehicle floats or is being driven through water, or when it is being driven through swampy terrains and sinks so deeply that the cooling air which is supposed to be discharged by the cooling air fan through the opening in the back end of the vehicle can no longer force back the water or the mud, the water or mud enters the compartment which houses the radiator and cooling air fan through the opening in the back end of the vehicle, so that the cooling air fan is impaired, or even becomes completely inoperative.
When the cooling air fan fails, regardless of the cause, the radiator is no longer cooled by cooling air, so that if the engine of the drive unit continues to be operated, and if no overheating protection is provided to switch off the engine, there exists the danger that the engine will overheat. As a result, the mission of the vehicle is impaired.
It is therefore an object of the present invention to improve the cooling apparatus of the aforementioned general type in such a way that continuous cooling of the radiator, through which the coolant of the drive unit flows, is assured regardless of the driving or floating state at any given time.